smoke coming out tailpipe of 1998 pontiac gtp
What color is the smoke? White may means a bad head gasket. Black is running too rich and blue is oil.
I can't tell I think it's black or blue
I would guess that your engine is burning oil. How is the oil consumption? How many miles on the engine?
Black is a rich air/fuel mixture (too much gasoline), blue is burning oil. White billowing "smoke" is water (coolant) and, on this engine will be a failed intake manifold gasket. The 3.8 rarely, if ever, will blow a head gasket. HTH. -Jim
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